Thanks for warning me on Tekken. I was really digging the character design and all in the upcoming Tekken 8 but given I possess dexterity of a 10 year old, I should probably skip it and fighting games in general.
The reason to play fighting games is strictly that you like the idea of honing the skill and playing competitive 1v1 matches to improve. Progression and reward is pretty different from other genres in this sense.
The main problem with Tekken is that it doesn't really document its systems with tutorials or a manual. Fortunately, YouTube will teach you more than enough. Tekken also tends to reward legacy knowledge more than most fighting games, so you'll probably find that Tekken 7 tutorials get you farther than you expect.